Rod-puller.



H. 0J DAVIDSON..

ROD FULLER.

APPLICATION- m50 APR.3.1916.

Patented Apr. 23, 1918.

` E@ l ll HARRY 0. DAVIDSON, CF CLEVELAND, OHIO, ASSIGNOB. TO THE HYDRAULIC PRESSED STEEL COMPANY, OF CLEVELAND, OHIO, A CORPORATION 0F OHIO.

ROD-FULLER.

Specification of Letters Patent.

Patented rkpr. 23, 191%.

Application filed Apri13, 1916. Serial No. 88,475.

i To all whom t may concern.'

Be it known that l, HARRY C. DAVIDSON, a citizen of the United States, residing at Cleveland in the county of Cuyahoga and State of Chio, have invented a certain new and usefulImprovement in Rod-Pullers, of.

rods are employed for tying the opposedV mold boards or plates of the form together' prior to and during the pouring operation and until the yconcrete has suiiiciently set to permit of the removal of the form.

lt is found more economical to pull the rods out of the wall so that they may be used repeatedly, than it is to leave them in the wall and cut off the protruding ends of the rods. ll'lowever, unless an effectual device is employed for the purpose, it is a diliicult task to withdraw the rods from the wall, due to the adhesion of the material to the rod.

It is the object of my invention to provide a highly etlicient, yet comparatively simple and cheap device which may be conveniently used for withdrawing tie rods from concrete walls.

To this end I construct a rod puller in accordance with the accompanying drawing wherein Figure 1 represents a section through a concrete wall, showing a tie rod partially withdrawn therefrom by the device of my invention; Fig. 2 is a longitudinal section through the rod puller; Fig. 3 is a section, on the line3-3 of Fig. 2, through the clamping element of the device; and Fig. 4 is a perspective view which includes the bearing end of the rod puller, and one ofthe form members against which the bearing end of the puller operates.

While 1 have shown my puller as used with a particular style of form, the same is of the type shown in the application of Stewart R. McKay, Serial No.` 872,648, filed November 17, 1914. lt is obvious that the puller may be employed with various kinds of forms, either wooden or metal, asfwill be more fully explained hereinafter; and while 1 will now proceed to describe the embodiment of my invention illustrated in the ac companying drawing, it will be understood that ,l do not limit myself to the structural details thereof further than is required by the terms of the annexed claims and is rendered necessary by the state of the prior' art.

ln the drawing, A. represents a poured .concrete wall, and B one of the uprights of a form or mold structure which, during the pouring operation, was tied to a corresponding member' on the opposite side of the wall, by means of the rod C. lt will be understood, of course, that suitable clamping collars embrace the rod and bearagainst the opposed faces of the form members to hold them against separation, during the pouring operation and subsequent setting process. After the wall has sufliciently set, these collars are removed, and a rod puller is `applied to the rod and the rod withdrawn from the wall.

The rod puller of my invention com.

prises a bearing element 1 having a threaded shank 2; a clamping element 3, having a threaded shank 4; and an elongated, tubular nut 5, having the opposed ends of its bore provided with threads of opposite inclination for cooperation with the threads of the shanks 2 and 4, the shankof the clamping element being herein shown as provided with a right hand thread, while the shank of the bearing element is provided with a left hand thread. |The exterior of the nut has a central wrench-receiving portion 8.

The body portion of the clamping element 3 is'in the form of a box, the end wall 9 whereof is provided with an aperture l0, while a corresponding aperture is formed in the opposite end wall 11 by the continuation of the bore 12, which extends longitudinally through the shank 4. The aperture 10 and bore l2 are circular and of a diameter somewhat greater than that of the rod C. A set screw 14 is threaded through the top wall of the clamping element in a position to bear upon the rod C substantially midway between the end walls of the element or, as may be better expressed, practically central of the biting lips formed at the inner ends of the aperture`10 and bore 12. Therefore, when the set screw 14 is screwed inward it will bend the rod C between the biting lips and thus firmly lock tially concentric with the shank.

lar plate or head to which the numeral l is applied, and the same is shown as substan- A bore 15 extends longitudinally through the member for the accommodation yof the rod C. The bearing face of the head 1, or that opposite the shank 2, is provided with barbs 16, two of such barbs preferably being em-Y ployed and located diametrically opposite each other. When the puller isused in connection with the McKay form hereinbefore referred to and shown in the drawing, the barbs 16 enter the notches which extend in opposite` directions from the openings through which the tie rods pass, and prevent the bearing element from turning. The clamping element is held against angular movement with respect to the rod by virtue of its clamping action thereon.

Therefore, when the rod puller is applied to the rod as illustrated with the bearing plate in engagement with the form, and a suitable wrench is applied to the nut 15 and the same turned in an appropriate direction, the bearing and the clamping elements of the device are separated, the latter element pulling the rod with it through the bearing element and from the wall.

wWhen the device is used in connection with wooden forms, the barbs 16 embed themselves within the wood, thus forming their own recesses, and effectually preventing the bearing element from turning when the nut 5 is operated.

Having thus described my invention, what I claim is:

1. In a Arod puller, the combination of a bearing element comprising a head having a shank and provided with a bore extending longitudinally through the shank and head, a clamping element comprising a hollow cas ing and a shank and having a bore extending longitudinally through the shank and casing, the interior of the casing constituting an enlargement of the bore, means within the casing for clampingit to a rod extending through the bearing element and clamping element, the shank of each element beying provided with an external thread that is oppositely inclined with respect to the thread of the other, and a nut having a bore'the opposite ends of which are threaded in reverse directions to ooperate with the threads of the Shanks.

2. In a rod puller, the combination of a bearing element comprising a head having a shank and provided with a bore extending longitudinallythrough the shank and head. a clamping element comprising a hollow casing and a shank and having ay bore extending longitudinally through the shank and casing, the interior of the casing constituting an enlargement of the bore, means within the casing for clamping it to a rod extendx ing through the bearing element and clamping element, the shank of each element being provided with a thread that is oppo sitely inclined with respect to the thread of the other, and a nut having opposed extensions which are threaded in reverse directions to coperatie with the threads of the Shanks, and having a bore in substantial alinement with the bores of the aforesaid elements.

3. In a rod puller, the combination of a` bearing element comprising a head having a shank and provided with a bore extending longitudinally through the shank and head, a clamping element comprising a hollow casing and a shank and having a bore extending longitudinally through the shank and cas* ing, the interior of the casing constituting an enlargement of the bore, means within the casing for clamping it to a rod extending through the bearing element and clamping element, the shank of each element being provided with an external thread that is oppositely inclined with respect to the thread of the other, and a nut having a through bore the opposite ends of which are threaded in rcverse directions to coperate with the threads of the shanks, the head of thebearing element having barbs for coperation with a member of a mold form to hold the bearing element against rotation.

4. In a rod puller, the combination of a bearing element comprising a head having a shank and provided with a bore extending longitudinally through the shank and head, a clamping element comprising a hollow casing and a shank and having a bore extending longitudinally through the shank and casing, the interior of the casing constituting an enlargement of the bore, means within the casing for clamping it to a` rod extending through the bearing element and clamping element, the shank of each element being provided with an external thread that is op positely inclined with respect to the thread of the other, a nut having a bore the opposite ends of which are threaded in reverse directions to coperate with the threads of the shanks, and means for holding the bearing element against rotation with respect to the rod.

In testimony whereof I hereunto aiiix my signature.

HARRY O. DAVIDSON.

Copies of this patent may be obtained for five cents each. by addressing the Commissioner of Patents,

. Washington, D. C. 

